1. Field of the Invention
The present invention relates to a neutral position indicator for indicating a neutral position of an electrically conductive cable coiled in the steering wheel in an automobile.
2. Description of the Relevant Art
Steering wheels in modern automobiles incorporate therein various electric circuit components such as a horn switch or an electric device such as a safety air bag system. Such automobiles are required to have a connector which keeps the circuit components or electric device on the steering wheel in electric contact with an electric circuit on a stationary component such as a steering column in the automobile body. One example of such a connector is a mechanical slip ring mechanism including slidable electric contacts which are held in sliding contact with each other to provide desired electric connection between the electric circuits desired to be electrically coupled. The slidable electric contacts are however poor in reliability as they are vulnerable to dust, water, or vibration.
U.S. Pat. No. 4,451,105 discloses an electrical connector device providing direct electric connection between relatively movable members in an automobile. In the disclosed device, a flat cable has one end connected to a steering wheel and the other end connected to a stationary member in the automobile body, the flat cable being wound around a steering shaft. The flat cable electrically interconnects an electric component in the steering wheel and an electric circuit in the automobile body. Since the flat cable provides stable electric contact between the desired electric circuits, it is highly reliable in operation.
The flat cable is required to be neutrally positioned in its coiled form when the steering wheel is in its neutral position, so that the flat cable can be wound and unwound in equal angular extents without being unduly pulled or tensioned at the time the steering wheel makes a few turns in opposite directions through a maximum steering angle. When assembling the steering wheel or reassembling the steering wheel after it has been repaired, therefore, it is necessary to indicate a neutral position for the flat cable so that the worker can easily set the flat cable in the neutral position in its coiled form. The disclosed electrical connector device has an arrangement for indicating the neutral position for the flat cable.
A similar neutral position indicator for a flat cable in a steering wheel is disclosed in U.S. Pat. No. 4,422,699.